This is the new standard in rifle accuracy and if you haven't heard about it, they have now paid H.P. White to test and certify both the accuracy and heat reduction. Teludyne StraightJacket Barrel System Video - YouTube
Its a little spendy. Not much benefit for the average shooter. With match ammo, I can shoot 1 moa with my 85 dollar barrel on my AR. If I was shooting competition, I would consider it.
The gas tube for the AR is integrated into the jacket... I wonder if you can replace it. It wouldn't make much sense if you couldn't.
I personally am not a good enough shooter to justify the cost of this system. For those who are, it's likely worth it to them.
New Tech always starts out all high dollar... the good news is once it becomes adopted that cost drops quickly... anyone else remember when those new finagled HD TV's first came out... $15,000 for a 50 inch... now what are they... just over one grand... this is just the start of what's to come... who can say what will happen in a few more years of development